Printers, scanners, multi functional peripherals (MFP), and other devices having network interfaces are being used widely in recent years. Such devices are used upon being coupled to a network along with computers and other devices and various management programs for managing these devices have been proposed.
For example, JP-A-2007-34445 describes using management information, referred to as a management information base (MIB) in a simple network management protocol (SNMP), which is one of the protocols for managing a device coupled to a network. The management information is used to identify a manufacturer of the device and is capable of managing the device of a specific type, for example, of a specific manufacturer.
A device that is to be subject to management may be produced by an original equipment manufacturer (OEM). As a manufacturer name and model of such a device made by an OEM, a company name and model of a company that sells the device (i.e., a distributor) are attached to the device rather than a company name and model number of a company that actually manufactures the device (i.e., the OEM maker). As a protocol for a device search in a network, a link layer topology discovery (LLTD) protocol has been proposed. According to the LLTD, data of an icon image (i.e., icon image data), used for displaying a network map, may be included in a response by a device.
In an inquiry using the MIB, it is possible to inquire about a plurality of information items with a single inquiry (i.e., an inquiry by a single packet). However, when a single packet is used, if the plurality of information items include even one information item that is not supported by a device, there is a disadvantage in that acquisition of all the information items, including the other information items (i.e., the supported information items), cannot be performed.
Among MIBs, there is a so-called private MIB, which is defined uniquely by a manufacturer. With this MIB, a manufacturer's unique information can be acquired. In device management using the private MIB, a device made by a different manufacturer from the manufacturer that defined the private MIB (i.e., a device made by an OEM is not included among devices made by the different manufacturer) does not support the private MIB and consequently cannot make a response. Thus, in a case where a single packet is used to inquire about a plurality of information items, including an information item acquirable by a private MIB, if a managed device does not support one private MIB, there is a disadvantage in that a managing device is caused to fail to acquire all information items, including the other information items that are in accordance with the supported MIBs, from the managed device. As a countermeasure for such a circumstance, it is possible to use a method of acquisition by execution of an inquiry for each information item using the MIB corresponding to the information item. With this method, failure to acquire information items that are in accordance with supported MIBs can be prevented.
However, if such a method is performed on all managed devices, the number of inquires increases. That is, as the number of managed devices on a network increases, the number of inquires also increases. Accordingly, even in the case in which a single packet may be used to manage a certain manufacturer's own device (i.e., including a device made by an OEM) that includes a plurality of information items, and the information items include an information item corresponding to a private MIB, there is a disadvantage in that an the number of inquires that must be executed by the MIB is proportional to the number of information items to be acquired.